Bluetooth headset - garbled voice + no voice memo recording

Hi,

I have a new Macbook Air running Catalina. When using my bluetooth headset (Bose QC35), facetime and zoom listeners complain that my voice is garbled. I can hear them fine. I have to switch to using computer speakers and microphone. This works fine but bothers my partner because he has to hear everything now. The bluetooth headset works fine on iphone, ipad, work laptop, etc.

In addition, I tried to use Voice Recorder to test the bluetooth microphone pick-up but found that doesn't work at all. Hitting the "record" button does not result in any recording activity. There was one note in the community to change setting in the midi audio settings. That did not work. This article describes what is happening: https://kirkville.com/voice-memos-on-macos-catalina-doesnt-record/

So, two problems, both related to sound on my new MacBook Air.